Technical Field of the Invention
This invention relates generally to communication networks and in particular to carrying Ethernet traffic and non-Ethernet traffic over the same medium.
Description of Related Art
The Common Public Radio Interface (CPRI) defines the protocol interface between the radio equipment control (REC) and the radio equipment (RE) in wireless basestations. Conventional basestations are located adjacent to the antenna, typically at the base of the antenna tower. However, finding suitable sites can be a challenge because of the footprint required for the equipment and the availability of power sources.
CPRI allows the use of a distributed architecture where basestations, containing the REC, are connected to remote radio heads via lossless fibre links that carry the CPRI data. This architecture reduces costs for service providers because only the remote radio heads containing the RE need to be situated in remote locations. The basestations can be centrally located in locations where footprint, climate, and availability of power are more easily managed.
Recently, a need has arisen to transmit Ethernet traffic over transport media used to carry CPRI traffic or other types of non-Ethernet traffic. However, Ethernet traffic requires constant bit-rate (CBR) channels with channel rates that can be configured between 30 MHz and 1 GHz. In addition, the original spacing between the packets needs to be maintained at the far end of the link.